1//===-- xray_powerpc64.cpp --------------------------------------*- C++ -*-===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8//
9// This file is a part of XRay, a dynamic runtime instrumentation system.
10//
11// Implementation of powerpc64 and powerpc64le routines.
12//
13//===----------------------------------------------------------------------===//
14#include "sanitizer_common/sanitizer_common.h"
15#include "xray_defs.h"
16#include "xray_interface_internal.h"
17#include "xray_utils.h"
18#include <atomic>
19#include <cassert>
20#include <cstring>
21
22#ifndef __LITTLE_ENDIAN__
23#error powerpc64 big endian is not supported for now.
24#endif
25
26namespace {
27
28constexpr unsigned long long JumpOverInstNum = 7;
29
30void clearCache(void *Addr, size_t Len) {
31 const size_t LineSize = 32;
32
33 const intptr_t Mask = ~(LineSize - 1);
34 const intptr_t StartLine = ((intptr_t)Addr) & Mask;
35 const intptr_t EndLine = ((intptr_t)Addr + Len + LineSize - 1) & Mask;
36
37 for (intptr_t Line = StartLine; Line < EndLine; Line += LineSize)
38 asm volatile("dcbf 0, %0" : : "r"(Line));
39 asm volatile("sync");
40
41 for (intptr_t Line = StartLine; Line < EndLine; Line += LineSize)
42 asm volatile("icbi 0, %0" : : "r"(Line));
43 asm volatile("isync");
44}
45
46} // namespace
47
48extern "C" void __clear_cache(void *start, void *end);
49
50namespace __xray {
51
52bool patchFunctionEntry(const bool Enable, uint32_t FuncId,
53 const XRaySledEntry &Sled,
54 const XRayTrampolines &Trampolines,
55 bool LogArgs) XRAY_NEVER_INSTRUMENT {
56 // TODO: Trampoline addresses are currently inserted at compile-time, using
57 // __xray_FunctionEntry and __xray_FunctionExit only.
58 // To support DSO instrumentation, trampolines have to be written during
59 // patching (see implementation on X86_64, e.g.).
60 const uint64_t Address = Sled.address();
61 if (Enable) {
62 // lis 0, FuncId[16..32]
63 // li 0, FuncId[0..15]
64 *reinterpret_cast<uint64_t *>(Address) =
65 (0x3c000000ull + (FuncId >> 16)) +
66 ((0x60000000ull + (FuncId & 0xffff)) << 32);
67 } else {
68 // b +JumpOverInstNum instructions.
69 *reinterpret_cast<uint32_t *>(Address) =
70 0x48000000ull + (JumpOverInstNum << 2);
71 }
72 clearCache(Addr: reinterpret_cast<void *>(Address), Len: 8);
73 return true;
74}
75
76bool patchFunctionExit(
77 const bool Enable, uint32_t FuncId, const XRaySledEntry &Sled,
78 const XRayTrampolines &Trampolines) XRAY_NEVER_INSTRUMENT {
79 // TODO: Trampoline addresses are currently inserted at compile-time, using
80 // __xray_FunctionEntry and __xray_FunctionExit only.
81 // To support DSO instrumentation, trampolines have to be written during
82 // patching (see implementation on X86_64, e.g.).
83 const uint64_t Address = Sled.address();
84 if (Enable) {
85 // lis 0, FuncId[16..32]
86 // li 0, FuncId[0..15]
87 *reinterpret_cast<uint64_t *>(Address) =
88 (0x3c000000ull + (FuncId >> 16)) +
89 ((0x60000000ull + (FuncId & 0xffff)) << 32);
90 } else {
91 // Copy the blr/b instruction after JumpOverInstNum instructions.
92 *reinterpret_cast<uint32_t *>(Address) =
93 *(reinterpret_cast<uint32_t *>(Address) + JumpOverInstNum);
94 }
95 clearCache(Addr: reinterpret_cast<void *>(Address), Len: 8);
96 return true;
97}
98
99bool patchFunctionTailExit(
100 const bool Enable, const uint32_t FuncId, const XRaySledEntry &Sled,
101 const XRayTrampolines &Trampolines) XRAY_NEVER_INSTRUMENT {
102 return patchFunctionExit(Enable, FuncId, Sled, Trampolines);
103}
104
105// FIXME: Maybe implement this better?
106bool probeRequiredCPUFeatures() XRAY_NEVER_INSTRUMENT { return true; }
107
108bool patchCustomEvent(const bool Enable, const uint32_t FuncId,
109 const XRaySledEntry &Sled) XRAY_NEVER_INSTRUMENT {
110 // FIXME: Implement in powerpc64?
111 return false;
112}
113
114bool patchTypedEvent(const bool Enable, const uint32_t FuncId,
115 const XRaySledEntry &Sled) XRAY_NEVER_INSTRUMENT {
116 // FIXME: Implement in powerpc64?
117 return false;
118}
119
120} // namespace __xray
121
122extern "C" void __xray_ArgLoggerEntry() XRAY_NEVER_INSTRUMENT {
123 // FIXME: this will have to be implemented in the trampoline assembly file
124}
125
126extern "C" void __xray_FunctionTailExit() XRAY_NEVER_INSTRUMENT {
127 // For PowerPC, calls to __xray_FunctionEntry and __xray_FunctionExit
128 // are statically inserted into the sled. Tail exits are handled like normal
129 // function exits. This trampoline is therefore not implemented.
130 // This stub is placed here to avoid linking issues.
131}
132

source code of compiler-rt/lib/xray/xray_powerpc64.cpp